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Pension Benefits - Summary of Pension Plan Assets Using Fair Value Hierarchy by Asset Class (Details) - USD ($) $ in Millions	Mar. 31, 2025	Mar. 31, 2024	Mar. 31, 2023
Pension Plans, Defined Benefit | Non-U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	$ 66	$ 171	$ 174
Pension Plans, Defined Benefit | Non-U.S. Plans | Investment Assets at Fair Value
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	32	141
Pension Plans, Defined Benefit | Non-U.S. Plans | Cash and cash equivalents | Investment Assets at Fair Value
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	7	7
Pension Plans, Defined Benefit | Non-U.S. Plans | Equity commingled funds | Investment Assets at Fair Value
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	12	20
Pension Plans, Defined Benefit | Non-U.S. Plans | Government securities | Investment Assets at Fair Value
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	6	4
Pension Plans, Defined Benefit | Non-U.S. Plans | Corporate bonds | Investment Assets at Fair Value
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	4	4
Pension Plans, Defined Benefit | Non-U.S. Plans | Annuity contracts | Investment Assets at Fair Value
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	0	103
Pension Plans, Defined Benefit | Non-U.S. Plans | Real estate funds and other | Investment Assets at Fair Value
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	3	3
Pension Plans, Defined Benefit | Non-U.S. Plans | Real estate funds and other | Assets held at NAV practical expedient
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	34	30
Level 1 | Pension Plans, Defined Benefit | Non-U.S. Plans | Investment Assets at Fair Value
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	8	7
Level 1 | Pension Plans, Defined Benefit | Non-U.S. Plans | Cash and cash equivalents | Investment Assets at Fair Value
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	7	7
Level 1 | Pension Plans, Defined Benefit | Non-U.S. Plans | Equity commingled funds | Investment Assets at Fair Value
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	0	0
Level 1 | Pension Plans, Defined Benefit | Non-U.S. Plans | Government securities | Investment Assets at Fair Value
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	1	0
Level 1 | Pension Plans, Defined Benefit | Non-U.S. Plans | Corporate bonds | Investment Assets at Fair Value
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	0	0
Level 1 | Pension Plans, Defined Benefit | Non-U.S. Plans | Annuity contracts | Investment Assets at Fair Value
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	0	0
Level 1 | Pension Plans, Defined Benefit | Non-U.S. Plans | Real estate funds and other | Investment Assets at Fair Value
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	0	0
Level 2 | Pension Plans, Defined Benefit | Non-U.S. Plans | Investment Assets at Fair Value
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	24	31
Level 2 | Pension Plans, Defined Benefit | Non-U.S. Plans | Cash and cash equivalents | Investment Assets at Fair Value
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	0	0
Level 2 | Pension Plans, Defined Benefit | Non-U.S. Plans | Equity commingled funds | Investment Assets at Fair Value
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	12	20
Level 2 | Pension Plans, Defined Benefit | Non-U.S. Plans | Government securities | Investment Assets at Fair Value
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	5	4
Level 2 | Pension Plans, Defined Benefit | Non-U.S. Plans | Corporate bonds | Investment Assets at Fair Value
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	4	4
Level 2 | Pension Plans, Defined Benefit | Non-U.S. Plans | Annuity contracts | Investment Assets at Fair Value
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	0	0
Level 2 | Pension Plans, Defined Benefit | Non-U.S. Plans | Real estate funds and other | Investment Assets at Fair Value
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	3	3
Level 3
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	0	103	$ 110
Level 3 | Pension Plans, Defined Benefit | Non-U.S. Plans | Investment Assets at Fair Value
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	0	103
Level 3 | Pension Plans, Defined Benefit | Non-U.S. Plans | Cash and cash equivalents | Investment Assets at Fair Value
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	0	0
Level 3 | Pension Plans, Defined Benefit | Non-U.S. Plans | Equity commingled funds | Investment Assets at Fair Value
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	0	0
Level 3 | Pension Plans, Defined Benefit | Non-U.S. Plans | Government securities | Investment Assets at Fair Value
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	0	0
Level 3 | Pension Plans, Defined Benefit | Non-U.S. Plans | Corporate bonds | Investment Assets at Fair Value
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	0	0
Level 3 | Pension Plans, Defined Benefit | Non-U.S. Plans | Annuity contracts | Investment Assets at Fair Value
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	0	103
Level 3 | Pension Plans, Defined Benefit | Non-U.S. Plans | Real estate funds and other | Investment Assets at Fair Value
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	$ 0	$ 0

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